1. Field of the Invention
The present invention relates to a light quantity control device for a camera.
2. Description of the Related Art
Conventionally, there has been known a light quantity control device for a camera. In the conventional light quantity control device, at lease two blades are movable supported in opposing directions in a linear manner relative to a bottom board having an opening, a rotational movement of a driving lever connected to these blades is changed to a liner movement, and the liner movement is outputted to the blades, thereby controlling the light quantity passing through the opening (see Japanese Patent Application Publication No. 5-241224).
However, in the conventional light quantity control device, since a direction of extending the driving lever and a direction of the blade moving are substantially parallel with each other, misalignment of the driving lever greatly and adversely affect misalignments of the blades. Specifically, when the quantity of the light passing through the opening is controlled, that is to say, when a desired diameter of the opening is maintained, such slight misalignment of the driving lever might greatly change the desired diameter of the opening. Therefore, in the conventional light quantity control device, it is necessary to set the position of the driving lever with high accuracy.